This invention relates broadly to devices to control vortex flow on and around the lift surfaces of aircraft, and more particularly to a vortex diffusion device to reduce drag due to such vortex flow during cruise, including cruise in the high subsonic speed regime of the aircraft where compressibility effects, notably those of locally supersonic flows, are a primary consideration.
Vortex flow around the aircraft lift surfaces or wings is particularly strong during take-off and landing, and remains sufficiently strong to contribute approximately 50% to cruise drag. Considerable effort has heretofore been devoted to dissipating such vortex flow during the cruise regime without undue emphasis on the take-off and landing flight regimes. However, a vortex dissipator which is designed for cruise may be even more effective at other times.